Intravenous therapy or IV therapy is the giving of liquid substances directly into a blood vessel. Such therapy may be intermittent or may be continuous and during the therapy a fluid conduit must be established into the vascular system of the patient and maintained.
The simplest form of intravenous access is a syringe with an attached hypodermic needle. The needle is inserted through the skin into a blood vessel, and the contents of the syringe are injected through the needle into the bloodstream. Since direct injection only allows for the delivery to a patient of a single dose of medication, where prolonged therapy using multiple doses is to the regimen, a more popular mode employs a peripheral IV line consisting of a short catheter (a few centimeters long) inserted through the patient's skin into a sealed engagement with a peripheral vein. A hub in sealed communication with the axial passage of the catheter is engaged on the distal end of the catheter and remains outside the patient's body, usually on the skin surface. In this position the hub can be connected to a syringe or an intravenous infusion line to communicate fluid to the bloodstream of a patient, or capped when not in use. The hub and engaged catheter thus allows for multiple treatments with the same line.
However, on many patients a more direct route to the central veins is required for medication, treatments, and imaging. Conventionally, a central venous line provides access for this purpose and consists of a catheter is inserted into a subclavian, internal jugular, or (less commonly) a femoral vein and advanced toward the heart until it reaches the superior vena cava or right atrium. Because all of these veins are larger than peripheral veins, central lines can be employed to deliver a much higher volume of fluid and can also have multiple lumens feeding the central line.
Implantable ports are a type of central venous line which does not employ an external connector positioned outside the patient's body. Instead, such implantable ports have a small reservoir which is covered with a flexible cover and the entire device is implanted under the skin of the patient. Once so implanted, medication is administered to the patient thereafter by placing a small huber needle through their skin, piercing the flexible cover of the port, and injecting the medication directly into the reservoir under the flexible cover. When the needle is withdrawn, the reservoir cover is formed of a material which reseals itself.
Since the implanted port reservoir cover can accept hundreds of needle piercings during its lifetime, it is possible to leave the ports in the patient's body for years. This helps avoid infection by leaving the skin barrier intact and over time is much less painful to the patient since they need not endure pokes and needle sticks and an incision required by exterior mounted ports.
A particular problem occurs for medical professionals when implantable ports are infused using power injection. Such infusions communicate the liquid into the implanted port under high pressure in order to move a large amount of liquid into the body of the patient in a short time. Such powered injection devices can communicate high pressure levels through the cover and into the reservoir of the implanted infusion port. The implanted port therefor must be rated for the anticipated high fluid pressure or a rupture of the port and related serious problems will occur.
Because the implanted port is positioned under the skin of the patient, it cannot be visually inspected during and after use. Consequently, it is hard for medical personnel to ascertain if in fact the implanted port is rated for high pressure and resulting high volume of the anticipated infusion to be given the patient. Hidden from view by the patient skin layer, it is not possible to examine the implanted port prior to use.
However, most medical protocols require two means of ascertaining the implanted port is high-pressure rated prior to using it for that purpose during a subsequent high pressure injection through the cover of the port. Currently, one means to ascertain the port pressure rating is where the patient's chart may be marked with the pressure rating on the hidden port, or the patient may wear an ID bracelet, or other means to denote that the implanted port is rated to the pressure to which it is about to be connected.
However, there is no means for visual confirmation of the implanted and skin-covered port's pressure rating by the medical professional. Consequently, they must depend upon the accurate charting and labeling by themselves and by other workers. With charts and bracelets being known to be less than accurate on occasions, or in cases where a chart indicates one pressure rating and a bracelet indicates another, it would be especially helpful to provide a fail-safe means to ascertain the pressure rating of the implanted port. In cases where the records and charts disagree, such a failsafe means would also prevent needless patient procedures to remove or replace implanted ports when two means of identification cannot be found.
As such, there exists a continual unmet need, for a means for medical professionals to visually identify that an implanted infusion port, hidden by skin and other patient tissue, is actually rated for the high pressure use for which it is about to be employed. Such a means of identification should be easy to employ, and allow for the use of the installed base of medial equipment already in hospitals and medical offices to lower costs and insure widespread easy deployment.
With respect to the above, before explaining at least one preferred embodiment of the invention in detail or in general, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangement of the components or the steps set forth in the following description or illustrated in the drawings. The various apparatus and methods of the invention are capable of other embodiments, and of being practiced and carried out in various ways, all of which will be obvious to those skilled in the art once the information herein is reviewed. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As a consequence, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for designing new X-ray or fluoroscope discernable markers, allowing for a power and a pressure rating verification of implanted infusion ports and the like, and for carrying out the several purposes of the present disclosed device and method. It is important, therefore, that the embodiments, objects and claims herein, be regarded as including such equivalent construction and methodology insofar as they do not depart from the spirit and scope of the present invention.